The Welsh Local Government Association said councils were doing their "utmost" to protect services for vulnerable people but faced "massive pressures".

Mr Thomas told the BBC's Sunday Politics Wales programme that taking mental health services back from charities and other contractors would "store up problems for the future because we're going to end up spending far more long-term and people are going to end up in hospital".

Jake Roberts, 21, from Milford Haven, who suffers from depression and anxiety, said: "If the authorities take over, people aren't going to feel like an individual - people are just going to feel like a number."

'Scale of cuts'

A spokesperson for Welsh councils said: "We completely understand those calls from across Welsh communities to invest now in order to avert future problems across a range of services.

"The problem is that the scale of cuts just does not allow for this."

In November the assembly's children, young people and education committee warned that mental health services for children and adolescents in Wales were struggling to cope with demand.

Ann Jones, who chairs the committee, said they wanted to get "the best for young people who are trying to access those services".